The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 06, 1990
Filed:
Apr. 12, 1990
Edmond O Fey, Vestal, NY (US);
Peter Haselbauer, Dettenhausen, DE;
Dae Y Jung, Endwell, NY (US);
Ronald A Kaschak, Vestal, NY (US);
Hans-Dieter Kilthau, Rottenburg-Baisingen, DE;
Roy H Magnuson, Binghamton, NY (US);
Robert J Wagner, Vestal, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Nodule formation in a continuous electroless copper plating system is minimized by independently controlling the dissolved oxygen contents on the plating solution in the bath and in the associated external piping. The level of dissolved oxygen in the plating tank is maintained at a value such that satisfactory plating takes place. At the point where the plating solution leaves the tank, additional oxygen gas is introducted into the solution so that the level of dissolved oxygen in the plating solution in the external piping is high enough to prevent any plating from taking place in the external piping and so that in the external piping the copper is etched or dissolved back into solution. At the end of the external piping, the dissolved oxygen level is reduced so that the dissolved oxygen level of the plating solution in the tank is maintained at the level where plating will take place.